Johann wild



Patented Mar. l4, I899.

J. WILD.

HEAD FOR CUMPASSES.

(Application filed Nov. 25, 1898.)

(No Model.)

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Jew/22 0i":

UNITED STATES PATENT OFFICE.

JOHANN WILD, or SUI-IR, SWITZERLAND, ASSIGNOR TO WILD & 00., or SAMEPLAOE.

HEAD FOR ,COMPASSES.

SPECIFICATION forming part of Letters Patent No. 621,006, dated March 14, 1899.

Application filed November 25, 1898. Serial No. 697.4 12. (No model.)

To all whom it may concern:

Be it known that I, J OHANN WILD, a citizen of the Swiss Republic, residing at Suhr, near Aarau,in Switzerland,have invented new and useful Improvements in Draftsinens Compasses or Dividers, (for which I applied for a patentin Switzerland on the 1st of September, 1898; in Germany on the 12th of September,

1898; in France on the 12th of September, 1898; in Austria on the 12th of September, 1898; in Great Britain on the 13th of September, 1898, and in Belgium on the 28th of October,1898,) of which the following-is a specification.

My invention relates to improvements in draftsmens compasses, and particularly to the means for adjusting the pressure at the pivot-points to give greater or less friction at the joint.

Compasses have heretofore been made in which the handle has the form of a yoke in which the hinged legs are held by means of pivot-screws and auxiliary locking-screws provided for said pivot-screws. This construction, though making a convenient and easily-operated instrument, is hard and inconvenient to adj ust,it being necessary to first loosen the locking-screws and then tighten the pivot-screws and lock them in place again by the locking-screws, thus causinga considerable loss of time and requiring a certain amount of skill. My invention provides means for regulating the friction between the compass-legs by a single screw, which need not be so small as to be easily lost nor require skill to adjust it.

In the accompanying drawings I have illustrated my invention, in which Figure l is an edge view of a compass, partly in section, showing the adjusting devices; and Fig. 2 is a side view of a compass constructed in accordance with my invention.

Like letters of reference refer to similar parts.

In the drawings, a and I) represent the legs of a compass, hinged at their larger upper ends. A steel friction-plate 19 carries the hinge-pin b which latter keeps the twolegs centered. The yoke, in which the hinged compass-legs are pivoted,comprises two members c and 0 into which near their ends are fastened the pivot-screws cl, on which the hinged compass-legs have motion and which members are hinged together at c by means of a pin or other suitable means. Each member c and c is provided with a lug 0 0 extending beyond the hinge-point c Into the adjacent faces of these lugs may be formed, as shown, grooves 0 tapering from their outer to their inner ends, which grooves when in juxtaposition form a conical hole, into which the tapering end of a screw g is adapted to fit and act as a wedge to force the lugs apart, thus causing the pivot-points to approach .each other and increase the friction at the hinge between the two legs. Over these lugs is placed the handle e, secured to the yoke C by means of a pin f, passed through its lower end and through the lugs near the hinge, leaving sufficient clearance between the pin f and the hole through the lugs to allow them to be wedged apart by the screw 9. I have shown the screw 9 as provided with a milled head and passing through the end of the handle; but it is obvious that the same may be countersunk or have any desired shape.

The operation of the adjusting device is as follows: In order to tighten the compasses, it is only necessary to turn the milled head of the screw g. The conical end enters the conical hole formed by the grooves 0 forces the lugs c and c apart, and causes the pivots to approach each other and take a firmer hold upon the hinged compass-legs.

WVhen an adjustable screw g, constructed and arranged for operation as shown in the drawings, is used, the described adjustment can be effected without the use of a screwdriver or key.

Having now described my invention, what I claim as new therein, and desire to secure by Letters Patent, is

1. Adraftsmans compass comprisinghinged legs, a two-part yoke whose members are hinged together and provided with conical pivot-points to which said legs are pivoted, and means acting upon the yoke members to vary the distance between their pivot-points, for the purpose set forth.

. 2. A draftmans compass comprising legs provided with heads perforated for the reception of a hinge-pin, a two-part yoke whose members are hinged together and provided with conical pivot-points fitting into the outer end of the perforations in the two legs, and means acting upon the yoke members to vary the distance between their pivot-points, for the purpose set forth.

3. A draftsmans compass comprising two legs hinged together, a two-part yoke whose members are hinged together and provided with conical pivot-points on which said legs are pivoted, said yoke members prolonged beyond their hinge-joint, and means acting upon the prolongations of the yoke members to Vary the distance between their pivotpoints, for the purpose set forth.

4. Adraftsmans compass comprisinghinged legs in combination with a yoke having two hinged members, pivots in each member of said yoke on which the hinged legs are pivoted, and means for wedging the yoke members together, substantially as described.

5. A draftsmans compass comprisinghinged legs, in combination with a yoke composed of hinged members, each member of which carries apivot-point, and a lug beyond the hinge, a handle adapted to fit over said ing, and an adjusting-screw in said handle adapted to regulate the distance between the ends of said members and thereby the distance between the pivot-points, substantially as described.

6. A d raftsmans compass comprising hinged legs, in combination with a hinged yoke formed of two members each member carrying a pivot-point, a lug beyond the hinge on each member, a handle adapted to fit over said lugs, a pin passing through the handle and lugs, and a screw in the end of said handle and adapted to wedge the extensions apart, substantially as described.

7. A draftsmans compass com prising hinged legs, in combination with a hinged yoke formed of two members, each member carrying a pivot-point, a grooved lug beyond the hinge on each member, a handle adapted to fit over said lugs, a pin passing through the handle and lugs, and a screw in the end of said handle and adapted to wedge the extensions apart.

In witness whereof I have hereunto set my hand in presence of two witnesses.

JOHANN WILD.

Vitnesses:

J os. GEIER, M. VEIT 

